Composition for treating and brightening cellulose fibers



United States Patent 2 Claims. (Cl. 260-294) ABSTRACT OF THE DISCLOSURE A composition for treating cotton contains a DAS-triazine brightener of the formula H soax N NH-CHz-CH-CH:

2 OH H a conventional textile improving resin and a cationic softener.

This application is a division of copending application, Ser. No. 366,635, filed May 11, 1964, now Patent No. 3,309,363.

This invention relates to an improved means of simultaneously brightening and improving cellulose fibers. More particularly, it relates to the provision of a new brightener which can be effectively applied to cellulose fibers such as cotton simultaneously with the application of conventional textile improving resins and cationic softeners. It relates further to the resulting cotton fibers.

Cotton fabrics are generally finished by treatment with resins which make the fibers crease-resistant and also impart good wash-and-wear properties. These resins may undesirably render the fabrics hard to the touch. It has become the practice to include in the resin-treating composition a material which counteracts this undesirable side effect. For this purpose, softeners, mostly of the cationic type, are employed. These softeners are generally quaternary ammonium salts which are soluble in the aqueous resin-treating solution.

In a typical operation the textile resin monomer of the amino-aldehyde (called also amino resin) or epoxy type, together with an acid-acting accelerator, is dissolved in an aqueous solution. To this solution is added the quaternary ammonium salt to serve as softener. A cotton fabric is padded in the solution and cured at elevated temperatures to produce the finished fabric. The fabric is creaseresistant and, at the same time, is soft.

If it is desired to treat the fabric with an optical brightener, this treatment normally has to be performed as a separate padding step, since most known optical brighteners are not effective in the presence of the cationic softener added to counteract the undersirable effects of the textile resin. Thus, until the present, it has been necessary to perform the optical brightening step separately from the simultaneous textile resin-cationic softener treating step. Separate treatments are undesirable, since they necessitate more paddin equipment, require more time, and, thus, raise the cost of the finished fabric. It is the object of the present invention to provide a new composition which permits the application of an optical brightener and a textile improving resin in the presence of a cationic softener. This and other objects have been accomplished in accordance with this invention by the discovery of the new compound of the formula:

This compound (or, equivalently, its ammonium or sodium or potassium salt) is surprisingly stable in an aqueous bath containing the conventional textile improving resins and cationic softeners. An aqueous padding bath having all three components leads to cotton fabrics which, in one step, are improved with respect to brightness, crease-resistance and softness. This is surprising since, as will be shown hereinafter, chemical structures which are presumably closely related and which are useful optical brighteners in the absence of the cationic softener, lose their effectiveness to a great extent in the presence of a cationic softener. The compound of the present invention retains its effectiveness substantially completely.

The brightener of this invention is made by reacting 2 moles of cyanuric chloride in an alkaline solution with one mole of 4,4-diaminostilbene-2,2-disulfonic acid, followed by treatment with 4 moles of l-aminopropanediol- 2,3. The alkali used is preferably a hydroxide of an alkali metal such as sodium. The solution of the alkali salt of a compound of this invention may be used directly in the resin-softener application or the compound may be isolated as the free acid and later dissolved with an alkali hydroxide before application.

The brightener of the present invention may be applied with conventional textile improving resins. The preferred resin monomer is an amino resin, a type of resin monomer well-known in the art (see I. F. Blais, Amino Resins, New York, Reinhold, 1959, Chapter 7), which is used together with an acid-acting accelerator, which can be a salt of a strong acid, like zinc nitrate, zinc fluoroborate, magnesium chloride, ammonium sulfate, diammonium phosphate, etc. The accelerator initiates polymerization at the curing stage.

Any conventional cationic softener useful with the above-described resins may be used herein. Generally and preferably, they are quaternary ammonium salts such as a tetraalkyl ammonium salt. Preferred members of this type re dialkyl dimethyl quaternary ammonium chlorides in which the alkyl is a fatty residue such as stearyl, coco or tallow radicals.

Cotton fabrics are treated in accordance with the present invention by conventional means except that the optical brightener and the resin-softener treatment will be accomplished simultaneously. As an example of a useful operating procedure, the cloth is passed through a padding bath containing approximately 0.1% of the brightener, 10.0% of a resin monomer (50% type), 2.0% of an accelerator (30% type) such as an acidic salt, 2.0% of a cationic softener (5% type) and 0.10% of a wetting agent. It is then nipped in a roller to about 65-80% pickup and dried at room temperature. It is finally cured for 12 minutes at 325 F. The resulting fabric has good dimensional stability and a good hand and with the brightener of this invention has outstanding whiteness.

In general, the brightener bath should contain from 0.01 to 1.0% of brightener based on the weight of the padding solution. On the same basis, the concentration of the cationic softener should be from 1 to of a 5% type.

The following examples, in which parts are by weight, are presented to illustrate further the present invention.

A solution is prepared containing:

18.5 grams 4,4'-diaminostilbene-2,2'-disulfonic acid 220 grams of water milliliters 5 N sodium hydroxide solution 100 milliliters acetone The solution is cooled to 0 C. and treated rapidly with a solution at 0 C. of 18.5 grams of cyanuric chloride in 150 milliliters of acetone. The reaction is exothermic, the temperature rising to about 10 C. The mixture is cooled to 0 C. and stirred at this temperature until the reaction is complete. A solution of 40 milliliters of 15% anhydrous sodium carbonate is added to bring the pH to about 5. The mixture is heated to C. and treated with 36.4 grams of 1-aminopropanediol-2,3. The acetone is stripped off and the remaining solution heated at reflux until the reaction is complete. The whole is cooled to ambient temperature, acidified with 5 N hydrochloric acid solution and the product filtered, washed with ether and dried. Yield is 51.1 grams of product; A is 345 m absorptivity at this wave length is 46.2.

Example 2 A solution of the compound of Example 1 is made by dissolving 100 mg. of the compound in 100 ml. of water with one drop of 30 Baum caustic soda solution and warming. The solution is cooled to ambient temperature, and there is added to the solution indicated amounts, on weight of the solution (O.W.S.), of the following:

Textile resin: 10% dimethylolurea Accelerator: 2% of a 30% solution of magnesium chloride Cationic softener: 2% of a 5% solution of distearyl.di-

methyl ammonium chloride in the form of a 70% paste.

Water is added to a volume of 200 ml. Concentration of the compound of Example 1 in the padding solution is 0.0 5%.

80 x 80 (threads to the inch) percale cotton, about two yards, is given one dip and nip. Pickup is 80% solution on the weight of the fiber. The padded cotton is cured for two minutes at 325 F.

A highly chromatic white fabric of good hand and good dimensional stability is obtained. It is as white as a sample of cotton fabric padded with a solution having the brightener in the same concentration, but neither a resin nor a cationic softener.

Example 3 When cotton is padded in a 0.05% padding solution of the brightener compound of Example 1 using the procedure of Example 2 and choosing one .each of the following components in any combination, equally good results are obtained:

(1) Textile resin:

(at) A resin having at least methylated hexamethylol melamine to give 12.5% O.W.S. (b) Dimethylolurea to give 10.0% O.W.S. (2) Accelerator:

(a) 30% aqueous zinc nitrate containing a small amount of an alkanolamine to give 2.0% O.W.S. (b) 30% aqueous solution of magnesium chloride to give 2.0% O.W.S. (3) Cationic softener:

(a) softener GW, sold by Proctor and Gamble, a quaternary ammonium salt, to give 2.0% O.W.S. (b) Distearyl dimethyl ammonium chloride to give 2.0% O.W.S.

Highly chromatic white cotton fabric is obtained in each case.

Example 4.-Behavior of brightener of Example 1 in the presence of excess cationic softener This example shows the stability of the compound of Example 1 in the presence of excess concentrations of cationic softener.

A 0.05% padding solution of the brightener of Example 1 is prepared as in Example 2. The solution includes the following instead of the resin, accelerator and softener recited therein:

Textile resin: 12.0% O.W.S. of a resin mixture which is at least 75 methylated hexamethylol melamine.

Accelerator: 2.4% O.W.S. of a 30% solution of magnesium chloride.

Cationic softener: 8.0% of a 5% solution of cationic softener GW of Procter and Gamble, a quaternary ammonium salt.

The padding and curing procedure is followed as in Example 2.

A cotton fabric of good hand and comparable brightness to that of Example 2 is obtained. This shows that the brightener behaves well in the presence of excess cationic softener.

Example 5 The compound of this invention is highly desirable in that it is stable in the presence of a cationic softener and remains in solution. Expectedly similar compounds lose strength in the presence of a cationic softener. Otherwiseuseful brighteners such as the last compound of the following table, even precipitate completely out of solution in the presence of a cationic softener. Thus, they cannot be used to treat cotton in the presence of a cationic softener.

Such compounds are shown in the following table. Effectiveness for use as a cotton brightener from a padding bath containing cationic softener is measured as the percent loss of strength, using as standard the dyeing obtained from a bath having neither cationic softener nor resin. The higher the loss, the less the effectiveness of the brightener.

TABLE =CHNHC c-z 1i 1'. SOaNa X Z Remarks OCH CH OH NHCH -CHCH Loses -30% strength in resin-cationic softener HO OH application.

CH CH, -OCI-I2CH OH -N 0 Loses 25% when applied as above.

CI'IZCfiZ CHZCIIZOH -OCH CHz(OOHzCHz),OCH CHzOH 1 N Loses when applied as above.

\CH2CH20H -NH-O(CH OH) Loses 30-40% as above; also discolors the cloth.

-OCHzCHzOH -NHC6H4-(SO Hm) Loses 30% when applied as above.

CH2CHzOH N -N IOH CH OH 20-30% loss when applied. as above.

CH cl-lzOH CHzCHzOI-I -NH -N 20-35% loss when applied as above.

\CI'IZCHQOH NI-ICH CH OH NHOH;CH OH Shows 20-30% strength loss from resin-softener application.

-NHC6H4-(SO Nap) NHCH CH2OH Precipitates in presence of cationic softener.

Whitening efiect totally lost.

I claim:

2. The composition of claim 1 wherein the textile resin 1. A composition for treating cotton consisting essen- 40 is an amino resin. tially of an aqeuous solution having an effective amount sufi'icient to impart crease resistance to said cotton of a thermosetting textile resin, an

tetraalkyl ammonium salt cationic softener and an effective amount of an optical hrightener of the formula:

SOaX N l NH-CHz-CH-CH:

of hydrogen, sodium, ammonium References Cited effective amount of a 2,956,898 10/1960 Fleck 252-8.75 x 3,052,570 9/1962 Polansky et al. 260--29.4 X 3,173,841 3/1965 Roth et a1 2528.75X 3,309,363 3/1967 B11611 260-240 FOREIGN PATENTS 705,406 3/1954 Great Britain.

OH OH HERBERT B. GUYNN, Examiner.

and potassium.

UNITED STATES PATENTS LEON D. ROSDOL, Primary Examiner. 

